PubMed HealthSearch

Biomedical subjects

P A Freeman

Publications and source records attributed to P A Freeman.

At least 19 recordsLinked to original sources

Factors affecting the use of immunization among urban settlement dwellers in Papua New Guinea.

This paper examines the importance of selected social factors in the acceptance of childhood immunization in urban settlements in Port Moresby, Papua New Guinea. The study found that the provision of information to mothers on when to start immunization and how often the child should be immunized were key factors in determining immunization status. Maternal education was found to be positively associated with knowledge of immunization, but was not significantly associated with actual immunization practice. Over 70% of the women studied found out when to attend for immunization from the local maternal and child health (MCH) staff, hence emphasizing their importance in disseminating information. If coverage is to be increased further in urban settlements with mobile populations, maximal use must be made of local community organizations to disseminate the key immunization information and for follow-up of newborns and infants new to the community. Efforts to encourage mothers to deliver under supervision should also continue as this is an important point of first contact for immunization.

Child, Preschool

Possible reasons for non-completion of immunization in an urban settlement of Papua New Guinea.

A study to identify possible reasons for non-completion of immunization among children was carried out in an urban settlement of Port Moresby. It was found that the children's mothers lacked basic understanding about immunization and the potential seriousness of immunizable diseases. There was also poor social interaction between health workers and the mothers. It is recommended that emphasis be placed also on the social aspects of immunization if widespread coverage is to be achieved.

Attitude of Health Personnel

Lower limb fractures in the chronic spinal cord injured patient.

Experience in managing 33 lower limb fractures in 25 chronic spinal injured patients is described. An increased awareness among patients and medical staff is required to avoid misdiagnosis. Effort should be made to ensure bone union in satisfactory position, recognising the different requirements of ambulant and non-ambulant patients. 'Soft pillow splints' were found to give the best results in all fractures other than those of the femoral neck. Operative treatment with antibiotic prophylaxis is only indicated to correct important deformity.

Adolescent

Hybrid FES orthosis incorporating closed loop control and sensory feedback.

A hybrid functional electrical stimulation (FES) orthosis is described, comprising a rigid ankle-foot brace, a multi-channel FES stimulator with surface electrodes, body mounted sensors, a 'rule-based' controller and an electro-cutaneous display for supplementary sensory feedback. The mechanical brace provides stability, without FES activation of muscles, for standing postures normally adopted by patients. This avoids inducing muscle fatigue during prolonged upright activity. However, stability is conditional upon the position of the ground reaction vector (GRV) relative to the knee joint. The finite state FES controller reacts automatically to destabilizing shifts of the GRV by stimulating appropriate anti-gravity musculature to brace the leg. The FES system also features a control mode to initiate and terminate flexion of the leg during forward progression. A simple mode of supplementary sensory feedback was used during the laboratory standing tests to assist the patient in maintaining a set posture. Preliminary results of laboratory tests for two spinal cord injured subjects are presented.

Adult

Augmentation of the Oswestry Parawalker orthosis by means of surface electrical stimulation: gait analysis of three patients.

The Oswestry 'Parawalker' orthosis has been supplied to 15 adult thoracic level complete paraplegic patients enabling them to achieve a reciprocal gait with an inherent low energy demand. In order to further off-load the work demands on the upper limb girdle musculature during ambulation, three of these patients have undergone electrical stimulation of the gluteal muscles in stance phase. This was shown to increase the stability of the adduction and also provided forward propulsion by driving the stance-leg into extension. Bilateral stimulation of the quadriceps muscles has been shown to facilitate standing and sitting in the orthosis. Using a Kistler force platform, the crutch impulse can be seen to be reduced by as much as 36%. We speculate that this leads to a similar order of reduction in the work done by the upper limbs in these patients.

Adult

Surgical stabilisation of the rheumatoid cervical spine. A review of indications and results.

We have reviewed 32 patients with rheumatoid disease of the cervical spine who underwent a total of 40 operations aimed at correcting instability and improving any associated neurovascular deficit. Apart from four patients with intractable pain, the main indication for surgery was progressive neurological impairment. Of the 32 primary operations, 19 (60%) were successful; the remainder failed to achieve their objective and there were two deaths in the immediate postoperative period. Of eight secondary operations performed for recurrence of symptoms or failure to relieve cervical myelopathy, only four were successful. Of nine operations for bony decompression to relieve cord compression from irreducible subluxation, only four were successful. The overall results show a success rate of 57% and a failure rate of 35% with early operative mortality in 8%. Indications for operation are discussed and earlier diagnosis is considered to be the key to improved results.

Aged

The long-term results of the Howse total hip arthroplasty. With particular reference to those requiring revision.

We present the results of 506 consecutive Howse hip arthroplasties with a minimum follow-up of 10 years. The mortality within one month of surgery was 0.79%. The early dislocation rate was 1.38%, two hips requiring revision. Nine hips developed deep sepsis (1.78%), eight of which required revision. At 10 years 42 hips (8.3%) had required revision, including 14 with aseptic acetabular loosening and 11 with femoral stem fractures. We feel that as judged by the dislocation rate and the need for subsequent revision, the Howse arthroplasty is an acceptable form of total hip replacement, particularly in the older patient and in those requiring total replacement for femoral neck fractures.

Adult

Bilateral hip and knee replacement in rheumatoid arthritis.

A series of 20 patients who had bilateral hip and knee replacement are reviewed and analyzed. Early surgical opinion should be sought before all four joints are irreparably destroyed and the patient is nonambulant so that the joints can be replaced one at a time, as necessary to maintain mobility. This considerably reduces stress to the patient, the surgeon, the nursing staff, and the rehabilitation team. The follow-up period ranged from 2 to 13 years. The early postoperative complications were few and the reoperation rate for aseptic loosening in this study was 3.75%.

Aged

Total knee arthroplasty in haemophilic arthritis.

The results of total knee replacement in five patients aged between 22 and 37 with severe haemophilia A or B are described. All patients had been managed conservatively without success. Frequent bleeds, severe pain and limitation of movement were the indications for operation. Despite close haematological surveillance, bleeding problems occurred in three of the patients and large quantities of plasma concentrates were required. Review of the patients over a period of 25 to 48 months after operation showed dramatic lessening of pain and maintenance of a satisfactory range of movement. The frequency of haemarthrosis diminished markedly and the requirements for factor concentrate in the years after operation fell substantially. Two patients returned to employment. Total knee replacement led to marked clinical improvement in all the patients, but the long-term results are not yet known.

Adult

Morphology of the gills of larval and parasitic adult sea lamprey, Petromyzon marinus L.

The general morphology of the gills is similar in larval (ammocoetes) and parasitic adult sea lampreys, Petromyzon marinus, despite different methods of ventilation necessitated by their feeding habits. The gill lamellae are supported by randomly-distributed pillar cells which enclose blood spaces and collagen columns. The distribution of these cells in lampreys is different from that of higher fishes and it may be inefficient for respiratory exchange. The presence of cytoplasmic microfilaments suggests that these cells have the ability to reduce the lamellar blood spaces through contraction. Marginal channels at the tips of the lamellae are lined only by endothelial cells. The thickness of the water-blood pathway in lampreys falls within the range described for higher fishes, with the most efficient gas exchange likely occuring at the lamellar tips where only a single layer of epithelial cells is present. The abrupt increase in height of the epithelium near the lamellar bases in adults, compared to the gradual transition in height along the lamellae in ammocoetes, is perhaps reflective of higher oxygen requirements during the parasitic stage. The consistent appearance of wide, lateral intercellular spaces within the respiratory epithelium of lampreys indicates possible involvement of these spaces in transport. Mucous secretion appears to be an important function of the superficial platelet cells in ammocoetes. "Mitochondria-rich" and "mitochondria-poor" superficial cells are observed in both ammocoetes and adults, with the mitochondria-rich cells more prevalent toward the lamellar bases. The possibility that at least some of these cells may be involved in absorption is discussed. Mitochondria-rich cells in the interlamellar region are morphologically different in ammocoetes and adults but all possess an abundance of smooth endoplasmic reticulum and hence resemble "chloride cells" of higher fishes. The similarity of these cells in the parasitic adult lamprey to chloride cells of marine fishes may reflect the potential of the adult lamprey to osmoregulate in salt water. A scarcity of these cells in ammocoetes and their resemblance to chloride cells in freshwater fishes may reflect the restriction of larval lampreys to a freshwater habitat.

Animals